Algorithms for searching defects in engineering structures using GPR (Review article, Part I)

Abstract

Relevance of the problem of the development of technical means (GPR) and algorithms for processing ultra-wideband signals follows from the wide range of possibilities that these means of non-destructive testing and remote sensing provides, together with the potential of modern computing tools and software. Of particular interest in this regard are the results obtained by using various effects associated with a change in the polarization state of both primary (probing) pulses and signals reflected from complex multilayer media to detect defects in them. This is due to the possibility of not only quickly detecting heterogeneities, but also with the relatively low cost of such work. The purpose of the work is a review of various technical means (pulsed georadars) and signal processing methods for detecting various internal inhomogeneities in plane-layered media. These heterogeneities include, in addition to various internal communications elements (cables) and technical elements (drainage pipes), also dangerous externally invisible defects - subsurface cracks and delamination (interruption of contact between the layers). Materials and methods. The paper provides an overview of methods developed by the author, among others, which are designed to solve primarily the practical problems of detecting subsurface inhomogeneities and defects in plane-layered media. The physical basis for the creation of these methods was the result of many years of research by the author related to the analysis of the polarization state of complex (including pulsed) signals scattered by various objects. Results. The basis of the considered results is made up of both scientific articles and patents of Ukraine for inventions and utility models obtained by the author. Conclusions. The review of the results and various methods presented in the article is another confirmation of the wide possibilities offered by new means of remote sensing and non-destructive testing. These tools include not only the devices themselves (elements for obtaining primary data), but also information processing algorithms and software, combined into a single methodology for collecting, processing and subsequent storage of data on the current state of the examined technical and natural objects.